#include <bits/stdc++.h>

using namespace std;
ifstream f("lca.in");
ofstream g("lca.out");
int n, p, x , y;
int m[20][100005];
vector<int> graf[100005];
int nivel[100005];

void Read()
{
    f>>n>>p;
    for(int i = 2;i <= n;++i)
    {
        f>>m[0][i];
        graf[m[0][i]].push_back(i);
    }
    for(int j = 1;(1 << j) <= n;++j)
        for(int i = 1;i <= n;++i)
            m[j][i] = m[j - 1][m[j - 1][i]];
}

void DFS(int nod,int lvl)
{
    nivel[nod] = lvl;
    for(vector<int>::iterator it = graf[nod].begin();it != graf[nod].end();++it)
        DFS(*it, lvl + 1);
}

int lca(int x,int y)
{
    if(nivel[x] < nivel[y])
        swap(x, y);

    int logx, logy;
    for(logx = 1;(1 << logx) < nivel[x];++logx);
    for(logy = 1;(1 << logy) < nivel[y];++logy);

    for(int k = logx;k >= 0;--k)
        if(nivel[x] - (1 << k) >= nivel[y])
            x = m[k][x];

    if(x == y)
        return x;

    for(int k = logy;k >= 0;--k)
        if(m[k][x] && m[k][x] != m[k][y])
            {
                x = m[k][x];
                y = m[k][y];
            }
    return m[0][x];
}

int main()
{
    Read();
    DFS(1, 0);
    for(int i = 1;i <= p;++i)
    {
        f>>x>>y;
        g<<lca(x, y)<<'\n';
    }
    return 0;
}